Compounded oil



April 16, 1946, G.- H. DENISON, JR., ETAL 2,398,416

COMPOUNDED OIL Filed ma 10, 1943 2300 2 k O: S O L) m a 0 .s 1.0 1.5 2.0 PERCENT DlLAURYL SELENIDE m 01L Fig.1 120 PERCENT OIL RiNB CLOGGINB 0 .5 1.0 1.5 2.0 PERCENT DILAURYL SELENIDE IN ON;

nv'vmrom George H. Denim/3dr. Pau/ C Com/if- ATTOR/Vfy Patented Apr, 16, 1946 COMPOUNDED 01L George H. Denison, Jr., and Paul C. Condit,

Berkeley, Calif., assignors, by mesne assignments, to California Research Corporation, San Francisco, Calif., a corporation of Delaware Application May 10, 1943, Serial No. 486,306

14 Claims.

This invention relates to the improvement of hydrocarbon oilsand the like. More particularly, this invention relates to the improvement of compounded hydrocarbon lubricating oils containing metal salts of organic or organo substituted inorganic acids, by incorporating in said compounded oils aliphatic selenides.

This application is a continuation-in-part of our copending applications Serial No. 432,040, filed February 23, 1942 (issued April 11, 1944 as U. S. Patent No. 2,346,155) and Serial No. 476,760, flied February 22, 1943.

It is an object sought in the art of .compounded motor oils to produce an oil which is stable to oxidation at high temperatures and in the presence of oxidizing gases under high pressure (as in the crankcases of internal combustion engines, especially of the Diesel type); which does not excessively corrode bearings, including copper-lead and cadmium-silver alloy bearings; and which maintains engine cleanliness and freedom from piston ring sticking.

Many compounding agents are available to accompllsh each of these functions separately. However, seldom is it sufiicient merely to add to an oil an antioxidant, a corrosion inhibitor, and a detergent to maintain engine cleanliness and freedom from piston ring sticking. To illustrate,

suppose a base oil is deficient from the standpoint of piston ring sticking and to it is added a detergent, such as a metal naphthenate. The piston ring sticking will be reduced but the stability of the oil toward oxidation may be unimproved while its tendency to corrode copper-lead bearings is often increased, especially if the base oil is a paramnic oil. If, then, to the thus compounded oil is added an antioxidant-corrosion inhibitor, for example, diphenylamine, the result cannot be predicted a priori, and oftener than not the resulting oil will not be greatly improved, may even be worse than the oil without the anti-oxidant-corrosion inhibitor. The reason for this behavior evidently is that the system to which the antioxidant-corrosion inhibitor is added is not base oil, for which prior experience and data are available, but is base oil plus detergent, which is quite a different system from the base oil alone.

It is an object achieved by the present invention to provide a class of anti-oxidants and corrosion inhibitors which will function in lubricating oil in conjunction with metal salt detergents to provide an oil which is improved in comparison with the base oil as to detergency without a marked increase in comparison with the base oil of corrosiveness and of instability toward oxidation.

succinic, alpha dodecyl maleic, alpha cetyl tar- It is also an object achieved by the present invention to provide an oil which is high in detergency and low in tendency to. oxidize and to corrode copper-lead and cadmium-silver bearings.

It is a still further object achieved by the present invention to provide a class of anti-oxidants and corrosion inhibitors which will function as such in the presence of metal salt detergents.

Other objects achieved by the invention will be apparent from the description.

By metal salt detergen is meant a metal (ineluding ammonium, substituted ammonium, and organo-metallic radicals) salt of an organic acid or an organo substituted inorganic acid, said metalsalt detergent having a metal-to-oxygen and/or a metal-to-sulfur linkage. Examples are the sodium, potassium, magnesium, calcium, barium, cadmium, zinc, aluminum, tinand nickel salts of the following acids:

ORGANIC ACIDS Fatty acids.-Lauric, palmitic, stearic, oleic, ricinoleic, licanic and chaulmoogric acids.

Ar l substituted fatty acids.-Phenyl stearic, benzyl stearic and benzal stearic acids.

Polar substituted aliphatic carbomylic acids. Alpha, beta and gamma chloro lauric, palmitic and stearic acids; alpha, beta and gamma hydroxy lauric, almitic and stearic acids; alpha, beta and gamma amino lauric, palmitic and stearic acids; alpha cetyl malonic, alpha hexadecenyl nitro, carboethoxyl, and chloro phenols.

Thiophenols.-Cetylphenyl mercaptan. ORGANO SUBSTITUTED INORGANIC ACIDS Oncmo Sunsrrrursn Acrns or PHOSPHORUS rowm) and phosphinous 'acids; in these formulae, R1 and R2 are radicals of hydrocarbon structure, and part or all of the oxygen may be replaced by sulfur.

In the above formulae, R1, R2, R3, X1, X2, X3 and X4 are as defined above, at least one B. being hydrogen and at least one other R being a radical of hydrocarbon structure. I

Organo substituted acids of sulfur.-Amyl, hexyl, 'decyl, phenyl and benzyl acid sulfates; amyl, hexyl, decyl, phenyl, cetylphenyl and cetyl anthracene sulfonates; and petroleum sulfonic acids.

Dithiocarbamic wc5ds.-Acids of the generi formula wherein R1 and R2 are selected from the group consisting of hydrogen and radicals of hydrocarbon structure; e. g., dibutyl, diamyl and diphenyl dithiocarbamic acids. Also, dithiocarbamates may be used in which the nitrogen is part of a ring, as in the dithiocarbamates produced by reacting piperidine, alkyl piperidines and reduced petroleum nitrogen bases with carbon disulfide in the presence of caustic alkali. The alkali salts may be used in accordance with the invention, but preferably the polyvalent metal salts, formed by double decomposition of the alkali salt and a water soluble polyvalent metal salt, are used.

The above illustrated and other metal salt detergents may be used in motor oils for a number of purposes. Usually detergency, such as the maintenance of cleanliness and freedom from sludge, gum and other carbonaceous deposits on cylinder and piston walls and piston rings and in piston ring slots, and freedom from piston ring sticking, is an object of adding these salts to motor oils. The oils may also be stabilized against oxidative and thermal deterioration by the presence of these salts. Also, combinations of these additives, such as organo phosphatephenate (e. g., calcium cetyl phosphate or thicphosphate plus calcium cetyl phenate or sulfurized calcium cetyl phenate) and sulfonatephosphate (e. g., calcium or zinc salts of cetyl phenyl, cetyl anthracene or petroleum sulfonic acids plus calcium cetyl phenyl phosphate, zinc cetyl thlopho'sphate, or zinc di- (methylcyclohlelgyl) thiophdsphate) may be added to motor 0 a In accordance with the present invention, hydrocarbon oils,in particular, hydrocarbon motor lubricating oils, are compounded with metal salt detergents and aliphatic selenides having in the molecule the structure wherein the carbon atoms are aliphatic carbon atoms and m is 1 or 2. One or more different metal saltdetergents and one or more different selenium compounds may be present in the oil.

Preferably, selenides containing at least 8 carbon atoms in at least one aliphatic radical attached to the group (Se)mare used; more advantageously those having at least 8 carbon atoms in both aliphatic radicals are used. The aliphatic groups may be like or unlike groups and they may be straight or branched open chain or cyclic aliphatic groups they may be saturated or unsaturated; and they may be substituted or unsubstituted, as by aromatic groups and by polar groups, such as halogen, amino, hydroxy, etc.

Examples of selenium compounds forming one component of the compositions of the present invention are as follows: dipropyl, dibutyl, diamyl, dihexyl, dioctyl, decyl methyl, didecyl, diundecyl, dilauryl, ditetradecyl, cetyl ethyl, octyl decyl, dicetyl, diheptadecyl, di-eicosyl, diparaflin, dibenzyl, bis (p-ohlorocetyl) and his (,B-hydroxycetyl) monoselenides (seleno ethers); dioctyl, didecyl, dilauryl, dicetyl, diheptadecyl and di-eicosyl diselenides; the various monoand poly-selem'des prepared by reacting sodium or other alkali metal monoor poly-selenides with halogenated, e. g., chlorinated hydrocarbons, such as decyl chloride, dodecyl chloride, tetradecyl chloride, cetyl chloride, heptadecyl chloride, eicosyl chloride, chlorinated lubricating oil and chlorinated wax. By "diparaflln selenides we mean selenides (monoand poly-selenides) of the character of those produced by condensing chlorinated wax with the app priate alkali metal selenide, e. g., sodium selenide.

Ways and means of producing aliphatic selenides capable of use in accordance with this invention are described in the aforesaid copending application Serial No. 476,760.

By way of illustrating the effects of the novel combinations of additives of this invention on motor oils, the following examples are provided:

Example 1.A Western SAE 60 aviation oil, with and without compounding agents, was submitted to test in a Lauson gasoline engine. The test was carried out as follows: A single cylinder Lauson gasoline spark ignition engine, 2 inch bore and 2 inch stroke, loaded with a threephase induction generator, was operated under extremely severe conditions designed to develop fully the tendency of the crankcase lubricant to deteriorate with gum formation and piston ring sticking. The engine was operated at 1200 revolutions per minute, the engine jacket temperature was maintained at 460 F., the crankcase oil temperature was maintained at 220 F. and the engine was operated for 30 hours after which the piston condition and the neutralization number of the used oil were determined. Results are set forth in Table I below:

2,898,416 3 Table I tion at 840 F. in an apparatus the type described by Dornte in "Industrial and Engineering D Percent Ring Neut. Chemistry," vol. 28, page 26 (1936) oxygen being Miditivcs J1 'ggggg 23$ L absorbed by the oil under test at 340 F., iron being present in the all during the test in the form of cast iron rods. The results are set forth St k.-- 1.30 if yl die'z'il'inide.--

e20... 0.24 in Table II below. The table shows the amount (3) 2 ggggmg; Stuck-0 52 or oxygen measured in cubic centimeters (S. T. cazretglphcsphizgte. "5 D F o z; m P.) absorbed by 100 grams of oil under test at 4 S in un ng as rem-.. 0 53 3313 2, aicer i sclethe times indicated.

n1 Table II (5) Same com undmg as 70 0 -..-do.-... 0.83

(3)+1.0% ilauryl sele- Additives l P. D. No. Piston Discoloration No.) as used in Table I above 025% Ca involves a careful inspection of the piston skirt and an estimate of Time, hrs. bill I 0 257 C 0 25 eecyl the percentage of the skirt covered with black, dark brown or light t a dds %1 phosphate+ brown gum. 0n the scale chosen a completely black piston is asee t I u: 0.25% signed a P. D. No. 01800 and a piston completely irec from diseolorap osp a e se en 0 an: 1 tion is assigned a P. D No. 01 0. Black gum on the piston skirt is Salem 6 estimated as being four times as detrimental to engine performance as light brown gum and a heavy deposit oi blacir gum was in many cases observed to be the forerunner of piston seizure. 030"" It will be noted from the data in Table I that 3;;3; dicetyl selenide and dilauryl selenide greatly im- (6-32. proved the characteristics of the phenate-phos- 1, phate compounding affecting deposition of mat- 3%- ter on the piston. This effect is even more strik- 1 1 ingly shown by the accompanying drawing. Referring to the drawing, in Fig. 1 abscissae 4m represent per cent by weight of dilauryl selenide 2 based on the finished oil and ordinates represent so 435"." P, D. No, In Fig. 2, abscissae represent per cent Example 3.Certain base oils and the same base oils compounded with certain metal salt detergents, with certain corrosion inhibitors of the invention and with both said metal salt detergents and said corrosion. inhibitors were subby weight of dilauryi selenide based on the finished oil and ordinates represent per cent oil ring slot clogging. In both Fig. 1 and Fig. 2 the curves are for Western SAE 60 aviation base oil compounded with 0.375% by weight of sulfurized calcium cetyl phenate and 0.125% by weight of calcium cetyl phosphate. The percentage of dila'uryl selenide varied as shown in The curves of Figs. 1 and 2 were plotted from data taken from Lauson engine runs carried out in the same manner as described above; the upper curve of Fig. 1 and the single curve of Fig. 2 refer to 60 hour Lauson runs, while the lower curve of Fig. 1 refers to hour Lauson Example 2.-An uncompounded oil (a highly refined Western parafilnic oil) and the same oil compounded with 0.25% calcium oetyl phosphate, with 0.25% dilauryl selenide and with 0.25% of each of said additives was submitted to oxidamitted to a strip corrosion test as follows: Glass tubes 2 inches in diameter and 20 inches long were immersed .in an oil bath, the temperature of which was automatically controlled to within :1 of the test temperature. Approximately 300 cc. of oil under test was placed in each tube and air was bubbled through it at the rate of 10 liters per hour. Strips of bearing metal were placed in the oil. The weight loss of each strip was recorded. Before weighing, each strip was washed in petroleum ether and carefully wiped with a soft cotton cloth. The duration of the test was 72 hours. Theresults are given in Tables III and IV below. The test temperature is inclicated at the head of each table.

Table III (325 F.)

Wt. loss Cu-Pb strips v15 incmse Neut. Naphtha F No. insolubles 24 hrs. 48 hrs. 72 hrs.

0.5% Ca cetyi phenate+0.25% Ca cetyl phosphate 34.1 88. 6, 106. 8 7. 4 1.03 28 0.5% Ca eetyl phenate+0.25% Ca cetyl phosphate+1% cetyl ethyl sulfide 7. 0 18. 6 21.8 9. 8 l. 58 14 0.5% Ca cetyl henate+0.25% 0a cetyl phosphate+0.2% dicetyl selemde 4. 2 9. 2 10. 6 2. 0 0. 96 0 0.5% sulfurizerPCa cetyl phenate+0.25% Ca cetyl phosphate 11.0 30. 5 44. 0 7. 6 1. 28 45 0.5% suliurized Ca cetyl phenate+0.25% Ca cetyl phosphate+l% oetyl ethyl sulfide. 4. 7 6. 4 8. 2 9. 2 l. 52 58 0.5% suiiurized Ca cetyl phenatei.-0.25% Ca cetyl phosphate+0.1% dicetyl selenide. 0. 1 +2. 5 l. 5 2. i 0.41 0

Table IV (300 F.)

Wt. loss of strips Vis. increase ser- 24 48 72 24 48 72 210. hrs hrs. hrs. hrs. hrs. hrs. F. F.

Nil 9 6.0 17.0 0.0 0.2 0.2 88 5. 2 1.39 9. 5 0.5% Ca cetyl phenate-. .6 52. 1 100. 5 l. 1 20. 1 103. 5 l5!) 7. 3 1.80 s 2 l7 dicetyl selenide .0 0. 4 2. 1 0. 2 0. 2 0. 3 53 2. 5 0. 57 i l dicetyl selenide phenate +1.4 3 6 6.0 0.2 0.2 0.2 47 L7 0. 23 2 Referring to Example 1, it will be noted that both dicetyl selenide and dilauryl selenide greatly reduced P. D. No., ring slot carbon and ring sticking and the neutralization number of the used oil below the values of the same criteria for the oil compounded with only, the sulfurized phenate and the phosphate.

Referring to Example 2, it is evident that in the presence of iron (iron being present under service conditions), the oxidation characteristics of the oil compounded with calcium cetylphosphate and dilauryl selenide system were very different from and much better than would be anticipated from the oxidation characteristics of oil compounded with the phosphate alone and of the oil compounded with the selenide alone. Referring to Example 3, Tables III and IV, it will be seen that the selenides effectively repressed the corrosiveness of oils compounded with metal salt detergents and were more efiective in this respect than the sulfides.

In Tables V and VI below are provided further data showing the beneficial eflects conferred by the selenides of the present invention upon oils containing various types of metal salt detergents. In the tables are shown cubic centimeters of oxygen (S. T. P.) absorbed at the times indicated by 100 grams of the oil under-test in the oxidator test described in Example 2. The test temperature is indicated at the head of each table.

structures:

Percentages of components of compounded oils herein and in the claims are percentages by weight based on the entire oil (oil plus additives) unless otherwise specified.

The combination of adclitives of the present invention may consist of one or more selenium compounds and one or more metal salt detergen Specific examples of combinations of the invention are as follows: 1. Dioctyl monoselenide 1. Ca cetyl phenate 2. Dilsuryl monoselenide 2. Sullurized Ca cetyl phenate 3. Dilauryl diselenide 3. Ca cetyl phosphate 4. Diparaifin selenide 4. Ca cetyl thiophosphste Al 6. Ca stearate A: 7. Cd cetylbonzoate A; 8. Ca naphthenate A; 9. Ca petroleum sulionate In the above table of combinations, An, where n=l, 2, 3, or 4, indicates the selenide'numbered 12 under heading A. Likewise, B, where n is an integer from 1 to 9, indicates the metal salt detergent numbered n found under heading B.

The additives of the present invention may Table V I Volume oxygen absorbed (340 F.) Base oil 2 hours 4 hours 6 hours 8 hours 10 hours 12 hours 14 hours 15 hours Solvent refined Nil 20 105 190 230 3 Western paraliinic.

0.5% Ca mahogany sulionate 380 0.5% Ca mahogany sulfonate+l% dilauryl selenide 0.5% suli'urized Ca eetyl phenate 0.5'7], sulfurized Ca cetyl phenate+1% dilauryl 0 se en e. 0.5% Ca cetyl phenate 0.5% Ca cetyl phenete+1% dilauryl selenide 20 0.5% A1 cetyl tartmte 40 0 .I5 Al cetyl tartrate+1% dilauryl selenide $2 1 0.9%Ce ce 0.9

selemde.

era-15951355555553:IIIIIIIII Qs cetyl ohydroxybenzoate+l% dilsuryl l The figure for oxygen absorbed by mixed base oil (no additives) is for the period of 3.5 hours.

1 The data in this table are taken from oxldator tests in which iron in the form of cast iron rod was present in the oil under test.

In the specific examples and tables above, di-

selenium compound are preferred. Higher concentrations of each, e. g., 10-30%. may be employed in producing concentrate for blending at later times with more oil to produce finished oils.

The chief field of utility of the additive combinations of the present invention is in motor oils for crankcase lubrication and the like, especially in Diesel, aircraft and other engines operating at high temperatures and pressures. However, the said combinations may be used advantageously in greases, cutting oils, transmission oils, heat transfer fluids, etc. Also, besides being used in the usual petroleum distillates having boiling ranges above the kerosene boiling range, the combination of additives of the present invention may be used in residual oils, polymer oils, oils from hydrogenation f coal and other carbonaceous matter, amyl naphthalene, etc.

The combination of ingredients of this invencetyl selenide, dilauryl selenide and cetyl ethyl 75 tion may be presentinhydrocarbon oils containl. A composition of matter comprising a major proportion of an oil of lubricating viscosity and a small amount each, sufficient to improve the oil, of a metal salt detergent and a compound having in its molecules the structure wherein the carbon atoms are aliphatic carbon atoms and m is 1 or 2.

2. A lubricant comprising a major proportion of a hydrocarbon oil of lubricating viscosity, 8. small amount, sufiicient to impart detergent properties to the oil, a metal salt detergent and a small amount, sumcient substantially to inhibit oxidation and corrosion, of an aliphatic monoselenide.

3. The lubricantof claim 2, wherein said metal is a polyvalent metal and said aliphatic monoselenide is dilauryl monoselenide.

4. The lubricant of claim 2, wherein said a1iphatic monoselenide is diparaflin selenide.

5. A petroleum lubricating oil comprising about 0.1 to 2% by weight of an oil-soluble polyvalent metal salt detergent and about 0.1 to 2% by weight of a selenide of the type wherein Bi and R2 are primary aliphatic radicals of aliphatic hydrocarbonsvranging from butane to parafliri wax,

6. A petroleum lubricating oil comprising about 0.1 to 2% by weight of an oil-soluble polyvalent metal salt detergent and about 0.1 to 2% by weight of a selenide of the type wherein R1 and R2 are primary aralkyl radicals.

'7. A liquid lubricant comprising a major proportion of hydrocarbon oil of lubricating viscossity, a small amount, sufilcient to improve the detergent properties of the oil, of an oil-soluble polyvalent metal phenate and a small amount,

amount, suflicient substantially to inhibit corrosion and oxidation, of an aliphatic monoselenide containing not less than eight carbon atoms in the molecule.

9. A liquid lubricant comprising a major proportion of hydrocarbon oil of lubricating viscosity, a small amount, sufllcient to improve the detergent properties of the oil, of an oil-soluble polyvalent metal salt of an organo-substituted acid of phosphorus and a small amount, sufilcient substantially to inhibit corrosion and oxidation, of an aliphatic monoselenide containing not less than eight carbon atoms in the molecule.

10. A compounded motor oil comprising a major proportion of petroleum lubricating oil and about 0.1 to 2% by weight each of dilauryl monoselenide, an oil-soluble polyvalent metal salt of an alkylated phenol and an oil-soluble polyvalent metal salt of an ester of a thiophosphoric acid.

11. A com ounded motor oil comprising a major proportion of petroleum lubricating oil and about 0.1 to 2% by weight each 0! a diaralkyl monoselenide, an oil-soluble polyvalent metal salt of an ester of a thiophosphoric acid and an oil-soluble polyvalent metal petroleum sulfonate.

12. A compounded motor oil comprising a maj or proportion of petroleum lubricating oil and about 0.1 to 2% by weight each of diparaflin monoselenide, an oil-soluble polyvalent metal etroleum sulfonate and an oil-soluble polyvalent metal salt of a reduced petroleum nitrogen base dithiocarbamate.

13. A concentrate useful for blending with further quantities of mineral oil to produce a finished product, comprising a concentrated disersion in mineral lubricating oil of a metal salt detergent and a compound having in its molecule the structure wherein the carbon atoms are aliphatic carbon atoms and m is 1 or 2.

14. A petroleum lubricating oil comprising about 0.1 to 2% by weight of an oil-soluble polyvalent metal salt detergent and about 0.1 to 2% by weight of a compound having in its molecule the structure Certificate of Correction Patent No. 2,398,416. April 16,1946.

v GEORGE H. DENISON, JR., ET AL. 1 It is hereby certified that error appears in the printed specification of the above numbered patent re uiring correction as follows: Page 5, first column, line 27, claim 4,

after the word sai insert metal is a polyvalent metal and said; and that the said Letters Patent should be read with this correction therein that the same may conform to the record of the case in the Patent Oflice.

Signed and sealed this 16th day of July, A. D. 1946.

[SEAL] LESLIE FRAZER,

First Assistant Commissioner of Patents. 

